Device, particularly for the rapid forging of workpieces of centrally symmetrical cross section



July 31, 1951 R DEVICE 2,562,644 RAPID FORGING OF WORKPIECES RICAL. CROSS-SECTION 6 A. SAXE PARTICULARLY FOR THE OF CENTRALLY SYMMET Filed Au Patented July 31, 1951 OFFICE DEVICE, PARTICULARLY FOR THE RAPID FORGING OF WORKPIECES OF CEN- TR'ALLY SYMMETRICAL CROSS SECTION August Saxer, Thalwil, Zurich, Switzerland Application August 6, 1948, Serial No. 42,758 In Switzerland August 15, 1947 The present invention relates to forging apparatus and particularly to a special construction and arrangement of hammer-like elements and their supporting bearings, which elements, distributed in multiple arrangement at definite angular distances over a circle or a circular area or lying over each other in stepped sets, uniforrnly and positively take part in the non-cutting shaping or forging of an axially symmetrical all, hammer-like workpiece-carriers supported in the manner of a cross-head are unsuitable for the slight travel and the high specific surface pressures. When it works in the manner of a crosshead, the workpiece-carrier has solelya reciprocating movement, and the front end of the connecting-rod makes a rotary swinging movement in the cross-head. Since in these constructions the known ballhead in the pan executes only slight movements which are unsuitable for forming a lubricating film, the head will in time seize in the pan, so that proper functioning of the device will become questionable.

It has therefore been proposed to avoid using the ballhead and pan by constructing the connecting-rod itself as workpiece-carrier and supporting this connecting-rod head in a sliding block, this latter having such a shape and construction that the connecting-rod head has free play to move. This device has proved thoroughly good in practice and is now adopted for use, no matter whether one is dealing with the forming of grooves in axially symmetrical workpieces, or Whether axially symmetrical workpieces are being given an external shape by rapid forging by means of this device, whereby either a profile-- circular or edges-is imparted to the workpiece through its diameter being altered, or grooves of various shape are pressed into it with the workpiece remaining stationary.

In practice, the above described arrangement has a drawback which indeed is not of such great importance because of the smallness of its spatial dimensions and of the great number of hammer blows, but which must be avoided in certain workpieces, namely the fact that the hammerhead executes a swinging movement round the 2' Claims. iCl. 78-21) middle of the workpiece which the workpiece does not completely follow. Practically, this results in a crumpling movement of the tool in or on the workpiece and therefore in a slight widening of the groove edges when such groove are being made, or in a rubbing on the periphery of the workpiece in the case of surface treatment-of such workpiece to achieve non-cutting shaping of the diameter. The aim and intention of the present invention i to remove this last drawback and at the same time to avoid using a'sliding block.

The essential characteristic of this invention consists in that the connecting rods (which carry the tools, or the heads of which are themselves formed to provide the tools) are arranged to slide ,in recesses of a carrier; said carrier being arranged'to follow the swingin movements of the connecting rods and, while so doing, to oscillate about its own central axis. 7

Here it should at once be noted that the invention is applicable to an arrangement with a single connecting-rod, but this can of course be increased in accordance with the aim required, so that several connecting-rods are distributed round the periphery, spaced at regular or irregular angular distances from each other, work in a carrier. No special shape-determining connection between the members of the connecting-rod drive and the carrier for the connecting-rod heads is required. since no canting can occur when the former are exactly adjusted with respect to the latter.

In accordance with a further feature of the invention, the connecting-rod support is constructed as a swinging disk in which the connectingrods themselves work in accordance with the purpose desired. This support is loosely pivotably supported and constructed'in such a way that the connecting-rods can easily be inserted.

A still further feature of the invention consists also in the workpiece being able to partake in the swinging movement of the holding member for the moving of the connecting-rods. Finally the device is also characterised by the workpiece being able to execute, in addition to the swinging movement, also an additional axial movement or a rotating or a combining rotating and axial movement.

The invention makes it possible for the hitherto necessary intermediate elements, such as sliding blocks and supporting of the connecting-rods in the sliding block, to be eliminated. This gives the advantage that there are fewer sources of defects and a considerably greater accuracy of working is obtained, which makes it possible to maintain close tolerances in the workpieces. Further, by the arrangement of the individual connecting-rods in the guiding of the swinging disk, the swinging movement of the former with respect to the workpiece i removed. In this way, an exact shaping of the workpiece in accordance with the shape of the tool is obtained.

The accompanying drawing shows by way of example one form of execution of the object of the invention diagrammatically, Fig. 1 being a section of the arrangement along the line I-I in Fig. 2 and Fig. 2 a section along the line IIII in Fig. 1.

As can be seen from the drawing, the numeral l designates the eccentric of one of the connecting-rods 2, of which several, for instance four can be provided arranged round the hole 3 receiving the workpiece 4. The eccentric I has two pins 5 which rotate in bearings 6 and drive the eccentric l. Each eccentric'is fitted in an eccentric strap 1 which is firmly connected to the connecting-rod 2 by a screw-cap 8. The connecting-rod head 9 is, for instance, suitably shaped with-four sides and slides as a holder of the tool 10 in a cor.- responding opening H in a carrier 12, which is here shown as a disk and is rotatably supported at 14 round the holes 3 for receiving the workpiece 4. As can be seen from Fig. 2, the carrier l2 has for instance four such openings Ii, each of which serves as a guideway for a hammer tool carrier 10 fitting exactly said opening H. The work-piece is held by a work holder l5 which, is designed in such a way that the workpiece, exactly like the carrier disk l2, partakes in the oscillatory movements within the limits of an angle which comprises only a few degrees. This angle corresponds to eccentricity of the eccentric I. In addition to the oscillatory movement, the work holder I5 is movable axially and rotationally,

What I claim is:

1. In apparatus for the rapid forging of workpieces of symmetrical cross-section, the combi-- nation of a base, a guide member rotatably mounted on the base and having a central hole to receive the work, a plurality of rotatable shafts disposed equidistant around said guide member with their axes parallel to one another and to the axis of said hole, an eccentric on each of said shafts and an equal number of hammer tool carriers slidably mounted on said guide member in angularly spaced relation around said holes, each of said tool carriers being slidable radially of the .guide member and having at its inner end a workengaging tool and at its outer end a sleeve rotatably engaging one of said eccentrics, whereby simultaneousrotation of said shafts produces reciprocation of the tool carriers and tools and oscillation of the guide member.

2. In apparatus for the rapid forging of workpieces, the combination of a base, a support for a work-piece, a guide member rotatably mounted on the base for rotation about the longitudinal axis of the work-piece, a tool carrier slidably mounted on the guide member for reciprocatory movement in a radial direction toward and away from the work-piece, a forging tool fixedly carried on the inner end of said carrier, a sleeve carricd on the outer end of said carrier, an eccentric carried on a shaft and rotatable in said sleeve, and bearing means for rotatably supporting said shaft, whereby rotation of the shaft and eccentric produces reciprocation of the tool carrier and tool and oscillation of the guide member about its axis of rotation.

AUGUST SAXER.

REFERENCES CITED UNITED STATES PATENTS Name Date Johanson Apr. 25, 1916 Numb r 

